Housing Style of Flange Mount Bearings

Flange bearings are bearings mounted in a cast iron flange and used with other bearing types. There are three basic styles: the round or square four-bolt, the tri-cornered three-bolt, or the diamond-shaped two-bolt. They can be used with ball bearings, plain bearings, needle roller and roller bearings. 

Two-bolt flange mount bearings are diamond shaped and have two holes for mounting bolts, one on each side of the bearing. A line drawn through the axis of the mounting holes forms a straight line that runs through the axis of the bearing. 

Three-bolt flange mount bearings have three mounting holes, either arranged radially around the bearing axis at 120 degrees from each other, or on a triangular flange that is offset from the bearing axis. 

Four-bolt flange mount bearings have four mounting holes, located radially around the bearing axis. Four-bolt flange mount bearings typically have round or square housings.